Cartridge closure with orifice strainer



April 10, 1956 c. w. MICKELSEN CARTRIDGE CLOSURE WITH ORIFICE STRAINER 3 Sheets-Sheet 1 Filed May 12, 195] w Z i a vv /g l. vg 7 M INVENTOR. CARL M/c/rase/v BY QM! TM April 0, 1956 c. w. MICKELSEN CARTRIDGE CLOSURE WITH ORIFICE STRAINER INVENTOR. CA2; 14/. M/CAELSE/V 3 Sheets-Sheet 2 Filed May 12, 195] A TTOQNEX April 10, 1956 Filed May 12, 195] C. W. MICKELSEN CARTRIDGE CLOSURE WITH ORIFICE STRAINER 3 Sheets-Sheet 3 INVENTOR. 634R; WM/cxa. 55v

United States Patent CARTRIDGE CLOSURE WITH ORIFICE STRAINER Carl W. Mickelsen, Verona, N. J., assignor to Pyrene C-O-Two Corporation, a corporation or" Deiaware Application May 12, 1951, Serial No. 226,067

4 Claims. (Cl. 16931) The present invention relates to closures for pressurizing cartridges and particularly to a closure for effecting a controlled discharge of the pressurizing medium protected against clogging by obstructions.

The closure is suitable for stored pressure medium cartridges including those used for pressurizing fire extinguishers of the type charged with an extinguishing agent, such as water, carbon tetrachloride, dry powder, etc., to expel the fire extinguishing agent. It is preferable that a controlled rate of discharge of the pressurizing medium be had so that at the start of the discharge when the container is practically filled with the fire extinguishing agent, only enough pressurizing agent is released to produce a safe pressure which is maintained practically constant in amount during the discharge. In achieving the controlled pressure, a metering orifice is generally used. It is very important that means be provided to prevent the orifice from becoming clogged with particles of mill scale or other foreign matter which may be in the cartridge. Heretofore strainers have been used to prevent the clogging of the orifice. However, they have been positioned so that during the charging of the cartridge, the entire charge must be passed through the strainer. If the strainer is of sufficiently small mesh so as to adequately protect the orifice against obstructions, a slow charge rate results unless excessively high charging pressures are used.

The present invention aims to overcome the difliculties and disadvantages of prior constructions by providing a container construction wherein charging is possible without passing the fluid through the strainer.

Another object of the invention is to provide a closure which is simple and economical in manufacture, eflicient in operation and durable in use.

In accordance with the invention this is accomplished by providing a unitary assembly of a closure member,

discharge control means and strainer means. The construction in accordance with the invention is advantageous in that an inexpensive assembly is provided as a throwaway unit, replaceable with a new assembly each time the cartridge is charged. This obviates the necessity of cleaning the orifice and strainer, thus overcoming any possible difl'iculty which may arise because of corrosion damage to the strainer, or in the case wherein very fine mesh screen is used, its obstruction from the imperceptible clogging resulting from a plurality of discharges therethrough. Furthermore, a construction is provided wherein the strainer may be inspected before each recharge. A further advantage is the provision of a construction whereby the recharge of the cartridge may be accomplished by comparatively unskilled labor.

Other objects of the invention will be apparent from the following description and accompanying drawings which show, by way of examples, embodiments of the invention.

In the drawings:

Figure 1 illustrates a fragmentary, vertical sectional I Patented Apr. 10, 1956 2 view of a fire extinguisher incorporating a cartridge having a closure made in accordance with the invention.

Figure 2 is an enlarged fragmentary view of a portion of Figure 1.

Figure 3 is an enlarged fragmentary view, corresponding to Figure 2, of a modified form in accordance with the invention.

Referring to the drawings, there is shown in Figure 1 a fire extinguisher 10 including a container 11 closed by a combination discharge head and carrying handle. The fire extinguisher is disclosed and claimed in co-pending Frank B. Allen application, Serial No. 167,220, filed June 9, 1950, now Patent No. 2,610,693, dated September 16, 1952. The container 11 is of the conventional type and may be made of any suitable material and shape to contain the extinguishing agent. An outlet is made adjacent the top end of the container for an elbow 15, a conventional discharge hose 16 being attached thereto by a fitting 17. Any suitable nozzle, not shown, may be attached to the end of the hose 16 to aid in directing the fire extinguishing agent to the fire. At the top of the container 11 is a filling opening 19 defined by a flange member 20 secured to the wall of the container 11 by a welded joint 21 or by other suitable means. The exterior of the flange member 20 is threaded as indicated at 22 to receive the discharge head and carrying handle 12. A carrying ring 24 is attached to body 25 of the discharge head 12 by supporting legs 26 spaced about the periphery of the ring handle.

The body 25 of the discharge head has a downwardly depending flange portion 27 to engage with the threaded exterior of the container flange member 2%. Apertures 29 are provided in the flange portion 27 to provide safety release of any pressure in the container 11 while the discharge head 12 is being removed therefrom. A sealing gasket is interposed between the top of the. flange member 20 and a shoulder 31 on the under side of the discharge head body 25 to provide a leakproof seal.

The extinguisher is pressurized by a stored fluid pressure medium cartridge 32 suitable for the storage of a compressed fluid such as carbon dioxide. In order to provide supporting means for the pressurizing cartridge 32, the discharge head body 25 has a downwardly depending tubuiar portion 3 having a threaded internal surface to engage with a corresponding threaded surface of a closure bushin 35 for the cartridge 32. The closure bushing and assembly is described and claimed in copending Frank B. Allen application Serial No. 137,847, filed January 10, 1950, now Patent No. 2,684,180 dated July 20, 1954 and includes the closure bushing 35 threadedly engaged in an outlet opening 36 of the cartridge 32. The bushing 35 has a shoulder or seat 37 about its passage 39 against which is received the edge of a metering thimble 4%? having an orifice 41 used to limit the rate of flow of fluid from the cartridge 32. A frangible sealing disc 42 is positioned against the edge of the thimble it) which acts as a gasket for the disc, to form an assembly which is secured in position by a ring or sealing disc nut 44 in threaded engagement with the inner end wall of the bushing 35. The ring or sealing disc nut 44 has longitudinally extending filling grooves 44:: cut through its threaded outer surface. Apertures 45 are made in the downwardly directed tubular portion 34 of the dis,- charge head body 25 adjacent its bottom side to provide passages for the release of the fluid from the cartridge 32.

In accordance with the invention strainer means 50 are provided adjacent the orifice 41 to prevent the obstruction thereof by foreign particles which may be carried by the pressurizing fluid medium. The metering thimble 49 is made of any suitable material so that its flange 51 is deformable to act asa sealing gasket between the shoulder or seat 37 and the frangible disc 42 yet of sufficient strength to support its downwardly directed tubular portion having a closed end 54 in which is positioned the orifice 41. in order to provide for the support of the strainer 50, the end of the tubular portion is thickened as indicated at 55'and formed with a recess 56 to receive the edge of the strainer 59. In a preferable construction the strainer is made of a dished form so as to provide more straining area than would be possible in the event a fiat strainer were to be used; The strainer is ecured in position by flaring its outer edge to form a flange 57 of a diameter so as to be received in the recess 56. An annular ring gasket 59 is then positioned over the strainer flange 57 and downwardly extending wall 63 of the recess 56 is spun or turned inwardly against the a ring gusset 59 to hold the strainer in position. 7

, In order to release the fluid pressure medium from the cartridge 32, puncturing means are provided operable from the exterior of the extinguisher preferably by inverting the extinguisher and striking the operating means against the surface such as the ground or floor. This is accomplished by providing an upwardly extending hollow extension 61 positioned approximately in the center of the discharge head body and extending upwardly through the ring handle 24. The extension 61 is made with an apertured partition 62 formed by making a portion of the opening through the extension of reduced diameter. An operating member 64 is positioned within the extension and is made with a downwardly depending portion forming a puncturing tip 65 adapted upon the downward movement of the operating member 64 to puncture the sealing disc 42. lealtproof seal, an O-ring gasket 66 is positioned in a recess about the operating member 64. To provide means to actuate the operating member 50, it is terminated in a cap member 6'7 secured thereto by a pin 69. In order to urge the operating member outwardly so that its puncturing tip 65 is spaced from the frangible disc 32, a spring 7% is positioned about the operating member 64 to about against the inner side of the cap member 67 and against the partition 62.

In some constructions the closure bushing may have at its lower or innermost end a second strainer 71 secured in position by an annular gasket 72 and turned-in end 7%. This strainer is of comparatively large mesh and does not appreciably aiiect the charging rate of the cartridge.

in charging or recharging a pressurizing cartridge 32 having a closure made in accordance with theinvention, the ring or sealing disc nut 44 is loosened and the bushing 35 attached to a conventional charging line. It will be seen that there is a passage for the incoming pressurizing fluid through the grooves 44a and between the seat 37 and the underside of the flange 51; thence, into the cartridge outwardly of the strainer Sil. The pressurizing fluid in its inward'passage does not flow through the strainer 56 and, thus, the cartridge is quickly charged using conventional low pressures. After being charged the cartridge is sealed by tightening the ring nut to close the passage past the seat 37.

In Figure 3 another embodiment of the invention is illustrated in which corresponding parts are designated by the same reference numerals as in Figures 1 and 2 with the addition of 1%. In Figure 3 there is shown a closure bushing with a unitary sealing disc and orifice member assembly which differs from the construction of the embodiment shown in Figures 1 and 2 in the structure of the metering thimble.

It has been found that when the metering thimble has been of copper difiiculty has been had in drilling the orifice opening in that there is a tendency for the copper to cause breakage of the very small drill used to provide the orifice of the desired diameter. In the construction used in Figure 3 means are provided to permit the use of a metal of any suitable harder material, such as brass,

'for'the wall of the orifice, and which may be drilled in order to provide a with less mechanical difiiculty than often occurs in the drilling of the small orifice hole through copper.

In the embodiment shown in Figure 3 a closure bushing is threadedly engaged in an opening 136 of the cartridge 132. As in the first embodiment, the bushing 135 has a shoulder or seat 137 about its passage 139 against which is received the edge of a metering thimble 140 which will be more fully described shortly. A frangible sealing disc 142 is positioned against the edge of the thimble 140 the edge of the thimble acting as a scaling gasket for the disc to form an assembly 143 which is held together by a ring or sealing disc nut 144 in threaded engagement with the inner end wall of the bushing 135. As in the first embodiment, the ring or sealing disc nut 144 has longitudinally extending filling grooves 144a cut through its threaded outer surface and apertures 145 are made in the downwardly directed tubular portion 134 of the discharge head body 125 adjacent its bottom side to provide passages for the release of the fluid from the cartridge 132.

T he metering thimble 14%) may be made of any suitable material such as copper so that its flange 151 is deformable to act as a sealing gasket between the shoulder or seat 137 and the frangible disc 142 yet of sufficient strength to support its downwardly directed. tubular portion 154 which has an open end. An annular shoulder 18%) is formed about the inner wall of the tubular portion 154. A cup-shaped orifice member 181 is adapted to be received in the tubular portion 154 and to have the edge of its closed end 182 abut against the shoulder 180. The cup-shaped member 181 is preferably made of brass or other suitable material to facilitate the drilling of the orifice 141 therein and its walls are made of a diameter so that it is received in position in the enlarged lower end of the tubular portion 154. In order to protect the orifice 141 against clogging a strainer is provided to fit against the open end of the cup-shaped orifice memher 181. As in the previous embodiment an annular ring gasket 159 is positioned over the edge of the strainer 150 and the downwardly extending wall 16% is spun or turned inwardly against the ring gasket 159 to hold the strainer 150 and orifice member 181 in position. The parts of the construction shown in Figure 3 are made of such dimensions as to be interchangeable with the construction shown in Figures 1 and 2.

This application is a continuation-in-part of my copending application Serial No. 179,688 filed August 16, 1950, now abandoned.

From the foregoing description it is apparent that a cartridge closure has been provided incorporating a unitary throw-away closure member, discharge control means and strainer which is readily rechargeable at a fast rate in as much as the incoming fluid medium bypasses the strainer. An assembly is provided for use with new cartridges or to convert a conventional pressurizing cartridge of the non-metering type to a cartridge of the metering type wherein the discharge therefrom is to be at a predetermined rate.

While the invention has been disclosed and illustrated with specific embodiments thereof, it will be understood that other embodiments may be resorted to without departing from the invention. For example, while the construction has been described and illustrated in connection with use of a sealing disc closure member, it is obvious that the novel construction might also be used with a valve member type closure. Also, while the strainer has been shown as made or" dished shape in one case, and as flat in another case, it is obvious that cylindrical or other shapes might well be used. Furthermore, while the strainer is shown as secured in position by spinning a wall of a recess to receive the edges of the strainer, it is obvious that other suitable constructions may be used. For example, the strainer might be welded into position or force fitted into its recess. Therefore, the form of the invention set out above should be considered illustrative and not as limiting the scope of the following claims.

I claim:

1. A metering closure for a stored fluid pressure medium cartridge adapted to be used with a puncturing member having a predetermined length of stroke, the cartridge having an outlet passage, means forming an outwardly turned seat about the outlet passage, the closure adapted to engage the seat and comprising a ring nut, a frangible disk, a flow limiting member of generally tubular shape, orificed end means for the lower end of the tubular member, strainer means carried by the flow limiting member protecting the orifice therein, and a flanged upper end for the tubular flow limiting member adapted to overlie the outlet seat and adapted to be urged thereagainst in cartridge closing relationship by the ring nut and frangible disk, the tubular member having a length greater than the length of stroke of the puncturing member, whereby upon the rupture of the frangible disk a metered discharge is had of the pressure medium stored in the cartridge, the flow limiting member and strainer of smaller diameter than the outlet passage so as to be removable outwardly from the outlet passage of the cartridge.

2. A metering closure for a stored fluid pressure medium cartridge adapted to be used with a puncturing member having a predetermined length of stroke, the cartridge having an outlet passage, means forming an outwardly turned seat about the outlet passage, the closure adapted to engage the seat and comprising a ring nut, a frangible disk, a flow limiting member of generally tubular shape, orificed end means for the lower end of the tubular member, means forming an annular recess on the lower end of the tubular member, a strainer secured by its edge in the recess and carried by the flow limiting member protecting the orifice therein, and a flanged upper end for the tubular flow limiting member adapted to overlie the outlet seat and adapted to be urged thereagainst in cartridge closing relationship by the ring nut and frangible disk, the tubular member having a length greater than the length of stroke of the puncturing member, whereby upon the rupture of the frangible disk a metered discharge is had of the pressure medium stored in the cartridge, the flow limiting member and strainer of smaller diameter than the outlet passage so as to be removable outwardly from the outlet passage of the cartridge.

3. A metering closure for a stored fluid pressure medium cartridge adapted to be used with a puncturing member having a predetermined length of stroke, the cartridge having an outlet passage, means forming an outwardly turned seat about the outlet passage, the closure adapted to engage the seat and comprising a ring nut, a frangible disk, a flow limiting member of generally tubular shape, an orificed end member for the lower end of the tubular member spaced from the lower edge thereof, a flat strainer carried by the tubular member at the lower end thereof protecting the orifice, and a flanged upper end for the tubular flow limiting member adapted to overlie the outlet seat and adapted to be urged thereagainst in cartridge closing relationship by the ring nut and frangible disk, the tubular member having a length to the orficed closure greater than the length of stroke of the puncturing member, whereby upon the rupture of the frangible disk a metered discharge is had of the pressure medium stored in the cartridge, the flow limiting member and strainer of smaller diameter than the outlet passage so as to be removable outwardly from the outlet passage of the cartridge.

4. A metering closure for a stored fiuid pressure medium cartridge adapted to be used with a puncturing member having a predetermined length of stroke, the cartridge having an outlet passage, means forming an outwardly turned seat about the outlet passage, the closure adapted to engage the seat and comprising a ring nut, a frangible disk, a flow limiting member of generally tubular shape, an inverted cup-shaped end member for the lower end of the tubular member, the end member having straight cylindrical walls and a flat disk-like end with an orifice therein, a flat strainer abutting the open end of the cup-shaped member, the lower end of the tubular member turned inwardly securing the end member and strainer in position in the tubular member, and a flanged upper end for the tubular flow limiting member adapted to overlie the outlet seat and adapted to be urged thereagainst in cartridge closing relationship by the ring nut and frangible disk, the tubular member having a length to the orifieed closure greater than the length of stroke of the puncturing member, the lower end of the ring nut turned inwardly securing the disk and flow limiting member in a unitary assembly, whereby upon the rupture of the frangible disk a metered discharge is had of the pressure medium stored in the cartridge, the flow limiting member and strainer of smaller diameter than the outlet passage so as to be removable outwardly from the outlet passage of the cartridge.

References Cited in the file of this patent UNITED STATES PATENTS 822,826 Coleman June 5, 1906 855,525 McNutt June 4, 1907 1,122,624 McNutt Dec. 29, 1914 1,919,149 Mapes July 18, 1933 1,974,254 Allen et al. Sept. 18, 1934 2,118,597 Ferguson May 24, 1938 2,547,954 Mapes et al. Apr. 10, 1951 2,560,407 Boal July 10, 1951 

